To blend a hydrophobic compound such as oil stably as an emulsion is an important technique in products such as cosmetics and perfumes. Generally, emulsified particles in an emulsion using a low-molecular surfactant are small and relatively stable, but in a solution system in the presence of a large amount of a surfactant such as detergent, their stability is lost and emulsification is destroyed. Accordingly, even if a hydrophobic compound useful for the surface of skin and hair to be washed is blended as an emulsion, the hydrophobic compound is emulsified with a surfactant used as a detergent, thus deteriorating foaming of the detergent. In this case, the intentionally blended hydrophobic compound is also emulsified with a surfactant used as the detergent, and thus almost all of the blended hydrophobic compound is washed away, so there is a problem that after use, the hydrophobic compound rarely remains on the washed surface.
Accordingly, JP-A 2003-226612 discloses an oil-in-water emulsion which is stable in a system in the presence of a large amount of a surfactant such as a detergent, that is, excellent in resistance to a surfactant solution, can be compounded with a detergent without deteriorating fundamental performance such as foaming, and is excellent in feel upon application onto the skin, as well as a process for producing the same.